Christian poetry is any poetry that contains Christian teachings, themes, or references. The influence of Christianity on poetry has been great in any area that Christianity has taken hold. Christian poems often directly reference the Bible, while others provide allegory.

Let this mind be in you, which was also in Christ Jesus:Who, being in the form of God, thought it not robbery to be equal with God:But made himself of no reputation, and took upon him the form of a servant, and was made in the likeness of men:And being found in fashion as a man, he humbled himself, and became obedient unto death, even the death of the cross.Wherefore God also hath highly exalted him, and given him a name which is above every name:That at the name of Jesus every knee should bow, of things in heaven, and things in earth, and things under the earth;And that every tongue should confess that Jesus Christ is Lord, to the glory of God the Father. (KJV)

Within the world of classical antiquity, Christian poets often struggled with their relationship to the existing traditions of Greek and Latin poetry, which were of course heavily influenced by paganism. Paul quotes the pagan poets Aratus and Epimenides in Acts 17:28: "For in him we live, and move, and have our being: as certain also of your own poets have said, 'For we are also his offspring.'" Some early Christian poets such as Ausonius continued to include allusions to pagan deities and standard classical figures and allusions continued to appear in his verse. Other Christian poems of the late Roman Empire, such as the Psychomachia of Prudentius, cut back on allusions to Greek mythology, but continue the use of inherited classical forms.

Other early Christian poets were more innovative. The hymnodist Venantius Fortunatus wrote a number of important poems that are still used in the liturgy of the Roman Catholic Church, such as the Vexilla Regis ("The Royal Standard") and Pange, lingua, gloriosi proelium certaminis ("Sing, O my tongue, of the glorious struggle"). From a literary and linguistic viewpoint, these hymns represent important innovations; they turn away from Greek prosody and instead seem to have been based on the rhythmic marching songs of Roman armies.

A related issue concerned the literary quality of Christian scripture. Most of the New Testament was written (or translated from a semitic language) in a sub-literary variety of koinêGreek, as was the Septuagint, the Greek translation of the Old Testament. The Old Latin Bible added further solecisms to those found in its source texts. None of the Christian scriptures were written to suit the tastes of those who were educated in classical Greek or Latin rhetoric. Educated pagans, seeing the sub-literary quality of the Christian scriptures, posed a problem for Christian apologists: why did the Holy Ghost write so badly? Some Christian writers such as Tertullian flatly rejected classical standards of rhetoric; "what has Athens to do with Jerusalem?" he asked.

The cultural prestige of classical literary standards was not so easy for other Christians to overcome. St Jerome, trained in the classical Latin rhetoric of Cicero, observed that dismay over the quality of existing Latin Bible translations was a major motivating factor that induced him to produce the Vulgate, which went on to become the standard Latin Bible, and remains the official Bible translation of the Roman Catholic Church. A fuller appreciation of the formal literary virtues of Biblical poetry remained unavailable for European Christians until 1754, when Robert Lowth (later made a bishop in the Church of England), kinder to the Hebrew language than his own, published Praelectiones Academicae de Sacra Poesi Hebraeorum, which identified parallelism as the chief rhetorical device within Hebrew poetry.

Modern Christian poetry especially suffers from a difficulty of definition. The writings of a Christian poet are not necessarily classified as Christian poetry. The themes of poetry are necessarily hard to pin down, and what some see as a Christian theme or viewpoint may not be seen by others. A number of modern writers are widely considered to have Christian themes in much of their poetry, including William Blake, G. K. Chesterton and T. S. Eliot.